A quantity zzz is built from two intermediate variables, and each intermediate depends on both xxx and yyy:
z=u2v,u=x+2y,v=xyz = u^2 v, \qquad u = x + 2y, \qquad v = xyz=u2v,u=x+2y,v=xy
What is ∂z∂x\dfrac{\partial z}{\partial x}∂x∂z at the point (x,y)=(1,2)(x, y) = (1, 2)(x,y)=(1,2)?
Select all that apply.
454545
202020
707070
656565